In order to reduce fuel consumption and limit pollutant emission in the exhaust gas, there is a tendency to feed internal combustion engines with increasingly weaker mixtures, which require the use of very precise and reliable devices for regulating the fuel metering and for controlling the mixture ignition, so as not to penalize engine efficiency, and to obtain the best performance over its entire range of operation.
Those control devices which currently best satisfy these requirements comprise programmed microprocessors, which also have the advantage of considerable versatility in use; with these devices, the microprocessor can control both the quantifying (numerical values) and the timing (control phasing) of the regulated quantities, and any required variation therein can be attained fairly simply by modifying the microprocessor programming.